1. Field of the Invention
The present invention relates to a mixer and to mixing rotors of the mixer which have a unique construction.
2. Description of the Prior Art
The prior art discloses many forms of mixers for mixing separate components into a homogeneous mixture. See, for example, the following U.S. Pat. Nos.: Bulley, 1,260,320; Pease, 2,048,286; Consalvo, 2,508,495; Colombo, 2,550,226; Simpson, 2,571,300; Kraffe De Laubarede, 2,631,016; Bridges, 2,947,524; and Hjelte, 3,064,908. Certain of the above patents disclose mixers including at least two mixing rotors that have spiraling screw configurations arranged in a meshing relationship with each other.
The rotors of a mixer must cause sufficient turbulent flow of the constituent components so they are thoroughly mixed with each other. The rotors must be relatively strong so that they can withstand the load to which they are subjected when mixing relatively viscous components. Such is the case when paints or the like are mixed for industrial use. Also, organic resin foams likewise are relatively viscous when mixed from their constituent comonents and must be thoroughly mixed before the foam begins to cure. Thus, the rotors must be driven fast enough so as to mix these foams prior to curing and must have sufficient strength to cause turbulent flow of the relatively viscous foam components.
Industrial mixers have not been completely satisfactory to date. The mixers either churn the components being mixed or cause them to remain stratified within the mixing chamber. Thus, a continuous mixing operation in a steady state manner with thorough mixing has not heretofore been achieved.